Graphene obtained by pyrolysis of alginate at 900 °C under inert atmosphere and exfoliation is used as a metal-free catalyst for reduction of nitro to amino groups with hydrogen as a reagent. The process is general for aromatic and aliphatic, conjugated and isolated nitro groups, and occurs with low selectivity over hydrogenation of carbon-carbon double bonds.

A bimodal (micro/mesoporous) COF was synthesized by coupling tetrakis-1,3,5,7-(4′-iodophenyl)adamantane with 4,4′-diethynylbiphenyl following a Sonogashira protocol.

Palladium is one of the most efficient metals for the hydrogenation of organic compounds. However, when molecules, such as nitroaromatics, with several reducible functionalities, are hydrogenated, Pd, like any other very active metal, such as nickel or platinum, often behaves unselectively. One strategy to render Pd more selective is to choose the proper support. Herein, we show that MAX phase powders of Ti3SiC2, Ti2AlC, or Ti3AlC2 can chemoselectively hydrogenate 4-nitrostyrene to 4-aminostyrene, with 100% selectivity, at around 3–4% conversion. To boost the latter, we loaded Ti3SiC2 with 0.0005 wt % Pd and increased the conversion to 100% while maintaining the 4-AS selectivity at >90%. By optimizing the Pd loading, we were also able to increase the turnover frequency 100-fold relative to previous literature results. The identification of this highly efficient and chemoselective system has broad implications for the design of cost-effective, earth-abundant, nontoxic, metal catalysts, with ultralow noble metal loadings.

Spirobifluorene‐based porous organic polymers (POP) were synthesized following two different protocols; the acetylenic coupling reaction conditions and the Sonogashira cross‐coupling reaction. These were utilized as support for the hydrogenation of a series of species containing unsaturated C=C and C=O bonds (4‐nitrostyrene, 4‐bromobenzophenone, acetophenone, 7‐nitro‐1‐tetralone and 1,2‐naphtoquinone confirmed their efficiency). POP1 prepared via a copper‐catalysis protocol was completely inactive, while POP2‐4 containing residual Pd exhibited different activities in accordance to the accessibility of the substrates to the metal. Further deposition of 0.5 wt% Pd led to active and stable catalysts. They were easily separated by filtration, and after re‐dispersion, afforded the same performances for ten successive cycles. This study also evidenced the specific role of the support in these reactions by comparing the behavior of Pd/POP with that of a Pd/C catalyst with the same loading of palladium. The deposition of Pt on these supports led to sub‐nanometric particles and, in accordance, to a different catalytic behavior reflected merely by differences in the selectivity.

the 3d transitional-metal oxides and oxyhydroxides and especially Ni-based materials have attracted considerable attention due to their low cost, easy availability, strong strength, better ductility, high corrosion resistance, good heat conduction, and high electrical conductivity. 15-32 Thus, Ni-based composite electrodes, such as NiP 2 , Ni chalcogenides, Ni (oxy)hydroxides or